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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Predominately zonal mid-level flow is expected over the CONUS by D2/Thursday. Stronger westerly flow is expected to gradually shift east as weak high pressure builds over the West. At the surface, a cold front is forecast to move across much of the plains ushering in a cooler air mass. Surface high pressure behind the front should keep winds modest over much of the central US. The only exception to this may be across parts of far northeast NM and southern CO. Here, the dry air mass may remain sheltered from the cold front supporting at least brief localized fire-weather conditions D2/Thursday afternoon. Otherwise, fire-weather potential appears limited across the CONUS. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Predominately zonal mid-level flow is expected over the CONUS by D2/Thursday. Stronger westerly flow is expected to gradually shift east as weak high pressure builds over the West. At the surface, a cold front is forecast to move across much of the plains ushering in a cooler air mass. Surface high pressure behind the front should keep winds modest over much of the central US. The only exception to this may be across parts of far northeast NM and southern CO. Here, the dry air mass may remain sheltered from the cold front supporting at least brief localized fire-weather conditions D2/Thursday afternoon. Otherwise, fire-weather potential appears limited across the CONUS. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...Synopsis... Behind the weakening upper low, flow aloft is forecast to trend more zonal and weaken as the general pattern de-amplifies. Still, some stronger westerly flow will linger over parts of the southern Rockies through the forecast period. A lee low will bolster low-level surface flow off the Rockies and into the adjacent High Plains this afternoon and evening. Warm temperatures are expected along with the dry downslope flow. This should support afternoon min RH values of 10-15% across much of eastern NM and southern CO. While winds are not expected to be overly strong (generally 10-15 mph) a few hours of dry and breezy conditions are possible. With area fuels dry, elevated fire-weather conditions are likely. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...Synopsis... Behind the weakening upper low, flow aloft is forecast to trend more zonal and weaken as the general pattern de-amplifies. Still, some stronger westerly flow will linger over parts of the southern Rockies through the forecast period. A lee low will bolster low-level surface flow off the Rockies and into the adjacent High Plains this afternoon and evening. Warm temperatures are expected along with the dry downslope flow. This should support afternoon min RH values of 10-15% across much of eastern NM and southern CO. While winds are not expected to be overly strong (generally 10-15 mph) a few hours of dry and breezy conditions are possible. With area fuels dry, elevated fire-weather conditions are likely. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...Synopsis... Behind the weakening upper low, flow aloft is forecast to trend more zonal and weaken as the general pattern de-amplifies. Still, some stronger westerly flow will linger over parts of the southern Rockies through the forecast period. A lee low will bolster low-level surface flow off the Rockies and into the adjacent High Plains this afternoon and evening. Warm temperatures are expected along with the dry downslope flow. This should support afternoon min RH values of 10-15% across much of eastern NM and southern CO. While winds are not expected to be overly strong (generally 10-15 mph) a few hours of dry and breezy conditions are possible. With area fuels dry, elevated fire-weather conditions are likely. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...Synopsis... Behind the weakening upper low, flow aloft is forecast to trend more zonal and weaken as the general pattern de-amplifies. Still, some stronger westerly flow will linger over parts of the southern Rockies through the forecast period. A lee low will bolster low-level surface flow off the Rockies and into the adjacent High Plains this afternoon and evening. Warm temperatures are expected along with the dry downslope flow. This should support afternoon min RH values of 10-15% across much of eastern NM and southern CO. While winds are not expected to be overly strong (generally 10-15 mph) a few hours of dry and breezy conditions are possible. With area fuels dry, elevated fire-weather conditions are likely. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MID MISSISSIPPI VALLEY AND LOWER OHIO VALLEY...AND OVER A PORTION OF NORTHERN TEXAS... ...SUMMARY... Scattered strong to severe storms capable of damaging winds, large hail, and perhaps a couple tornadoes will be possible Thursday from parts of eastern Missouri into the lower Ohio Valley and vicinity. Locally damaging winds and hail are also expected over parts of northern Texas. ...Synopsis... On Thursday, an upper low will move east from Manitoba into western Ontario, with a broad area of cyclonic flow aloft from the northern Plains to the Upper Great Lakes. South of the primary midlevel temperature gradient, moderate winds to around 50 kt will extend southward from MO into the OH Valley, with 30 kt midlevel winds into northern TX. Southwest winds of 30-40 kt will exist around 850 mb, aiding theta-e advection into the Mid MS/OH Valleys. At the surface, a cold front will exist roughly from northern MO into northwest TX Thursday morning, with a weak low moving from MO into the OH Valley ahead off the front. A warm front will lift northward ahead of the low, allowing moistening to occur over much of southern IL, IN, and northern KY during the day, and spreading into western OH overnight. Ample moisture ahead of this front will result in an elongated area of strong to severe potential throughout the day. ...Mid MS Valley into the lower OH Valley... Severe probabilities have been shifted farther west given latest model trends, as strong to severe storms could begin rather early in the day. Ongoing areas of storms are expected on the nose of the low-level jet, possibly in the form of an MCS, roughly over northern MO. As the warm front lifts north ahead of any such system, this could prove favorable for a swath of damaging winds. Otherwise, activity is expected to form near the low and along the cold front, where instability and shear will also favor supercells with large hail and perhaps tornado risk. Given the potential for early storms, this lends uncertainty to the forecast, and precludes an upgrade of higher coverage probabilities as placement would be uncertain. Regardless of early day evolution, moderate westerlies atop the expanding moist sector should favor areas of damaging wind, hail, and perhaps a few tornadoes during the day and through early evening. The severe risk could potentially reach into western OH and northern KY late, depending on upstream evolution. ...Northern TX... A cold front will push quickly south across OK and MO during the day, and across the Red River during the late afternoon and early evening. Given the late frontal arrival, strong destabilization will occur with full heating and upper 60s to lower 70s F dewpoints. MLCAPE over 3000 J/kg is forecast, with steep lapse rates through a deep layer. Although shear will not be strong, hodographs will favor southeastward-moving cells developing near the front or within the narrow low-level lapse rate plume where it will become uncapped. Locally damaging downbursts along with hail will be possible with any storms that develop, warranting an upgrade in severe probabilities for this focused diurnal event. ..Jewell.. 04/17/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MID MISSISSIPPI VALLEY AND LOWER OHIO VALLEY...AND OVER A PORTION OF NORTHERN TEXAS... ...SUMMARY... Scattered strong to severe storms capable of damaging winds, large hail, and perhaps a couple tornadoes will be possible Thursday from parts of eastern Missouri into the lower Ohio Valley and vicinity. Locally damaging winds and hail are also expected over parts of northern Texas. ...Synopsis... On Thursday, an upper low will move east from Manitoba into western Ontario, with a broad area of cyclonic flow aloft from the northern Plains to the Upper Great Lakes. South of the primary midlevel temperature gradient, moderate winds to around 50 kt will extend southward from MO into the OH Valley, with 30 kt midlevel winds into northern TX. Southwest winds of 30-40 kt will exist around 850 mb, aiding theta-e advection into the Mid MS/OH Valleys. At the surface, a cold front will exist roughly from northern MO into northwest TX Thursday morning, with a weak low moving from MO into the OH Valley ahead off the front. A warm front will lift northward ahead of the low, allowing moistening to occur over much of southern IL, IN, and northern KY during the day, and spreading into western OH overnight. Ample moisture ahead of this front will result in an elongated area of strong to severe potential throughout the day. ...Mid MS Valley into the lower OH Valley... Severe probabilities have been shifted farther west given latest model trends, as strong to severe storms could begin rather early in the day. Ongoing areas of storms are expected on the nose of the low-level jet, possibly in the form of an MCS, roughly over northern MO. As the warm front lifts north ahead of any such system, this could prove favorable for a swath of damaging winds. Otherwise, activity is expected to form near the low and along the cold front, where instability and shear will also favor supercells with large hail and perhaps tornado risk. Given the potential for early storms, this lends uncertainty to the forecast, and precludes an upgrade of higher coverage probabilities as placement would be uncertain. Regardless of early day evolution, moderate westerlies atop the expanding moist sector should favor areas of damaging wind, hail, and perhaps a few tornadoes during the day and through early evening. The severe risk could potentially reach into western OH and northern KY late, depending on upstream evolution. ...Northern TX... A cold front will push quickly south across OK and MO during the day, and across the Red River during the late afternoon and early evening. Given the late frontal arrival, strong destabilization will occur with full heating and upper 60s to lower 70s F dewpoints. MLCAPE over 3000 J/kg is forecast, with steep lapse rates through a deep layer. Although shear will not be strong, hodographs will favor southeastward-moving cells developing near the front or within the narrow low-level lapse rate plume where it will become uncapped. Locally damaging downbursts along with hail will be possible with any storms that develop, warranting an upgrade in severe probabilities for this focused diurnal event. ..Jewell.. 04/17/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MID MISSISSIPPI VALLEY AND LOWER OHIO VALLEY...AND OVER A PORTION OF NORTHERN TEXAS... ...SUMMARY... Scattered strong to severe storms capable of damaging winds, large hail, and perhaps a couple tornadoes will be possible Thursday from parts of eastern Missouri into the lower Ohio Valley and vicinity. Locally damaging winds and hail are also expected over parts of northern Texas. ...Synopsis... On Thursday, an upper low will move east from Manitoba into western Ontario, with a broad area of cyclonic flow aloft from the northern Plains to the Upper Great Lakes. South of the primary midlevel temperature gradient, moderate winds to around 50 kt will extend southward from MO into the OH Valley, with 30 kt midlevel winds into northern TX. Southwest winds of 30-40 kt will exist around 850 mb, aiding theta-e advection into the Mid MS/OH Valleys. At the surface, a cold front will exist roughly from northern MO into northwest TX Thursday morning, with a weak low moving from MO into the OH Valley ahead off the front. A warm front will lift northward ahead of the low, allowing moistening to occur over much of southern IL, IN, and northern KY during the day, and spreading into western OH overnight. Ample moisture ahead of this front will result in an elongated area of strong to severe potential throughout the day. ...Mid MS Valley into the lower OH Valley... Severe probabilities have been shifted farther west given latest model trends, as strong to severe storms could begin rather early in the day. Ongoing areas of storms are expected on the nose of the low-level jet, possibly in the form of an MCS, roughly over northern MO. As the warm front lifts north ahead of any such system, this could prove favorable for a swath of damaging winds. Otherwise, activity is expected to form near the low and along the cold front, where instability and shear will also favor supercells with large hail and perhaps tornado risk. Given the potential for early storms, this lends uncertainty to the forecast, and precludes an upgrade of higher coverage probabilities as placement would be uncertain. Regardless of early day evolution, moderate westerlies atop the expanding moist sector should favor areas of damaging wind, hail, and perhaps a few tornadoes during the day and through early evening. The severe risk could potentially reach into western OH and northern KY late, depending on upstream evolution. ...Northern TX... A cold front will push quickly south across OK and MO during the day, and across the Red River during the late afternoon and early evening. Given the late frontal arrival, strong destabilization will occur with full heating and upper 60s to lower 70s F dewpoints. MLCAPE over 3000 J/kg is forecast, with steep lapse rates through a deep layer. Although shear will not be strong, hodographs will favor southeastward-moving cells developing near the front or within the narrow low-level lapse rate plume where it will become uncapped. Locally damaging downbursts along with hail will be possible with any storms that develop, warranting an upgrade in severe probabilities for this focused diurnal event. ..Jewell.. 04/17/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MID MISSISSIPPI VALLEY AND LOWER OHIO VALLEY...AND OVER A PORTION OF NORTHERN TEXAS... ...SUMMARY... Scattered strong to severe storms capable of damaging winds, large hail, and perhaps a couple tornadoes will be possible Thursday from parts of eastern Missouri into the lower Ohio Valley and vicinity. Locally damaging winds and hail are also expected over parts of northern Texas. ...Synopsis... On Thursday, an upper low will move east from Manitoba into western Ontario, with a broad area of cyclonic flow aloft from the northern Plains to the Upper Great Lakes. South of the primary midlevel temperature gradient, moderate winds to around 50 kt will extend southward from MO into the OH Valley, with 30 kt midlevel winds into northern TX. Southwest winds of 30-40 kt will exist around 850 mb, aiding theta-e advection into the Mid MS/OH Valleys. At the surface, a cold front will exist roughly from northern MO into northwest TX Thursday morning, with a weak low moving from MO into the OH Valley ahead off the front. A warm front will lift northward ahead of the low, allowing moistening to occur over much of southern IL, IN, and northern KY during the day, and spreading into western OH overnight. Ample moisture ahead of this front will result in an elongated area of strong to severe potential throughout the day. ...Mid MS Valley into the lower OH Valley... Severe probabilities have been shifted farther west given latest model trends, as strong to severe storms could begin rather early in the day. Ongoing areas of storms are expected on the nose of the low-level jet, possibly in the form of an MCS, roughly over northern MO. As the warm front lifts north ahead of any such system, this could prove favorable for a swath of damaging winds. Otherwise, activity is expected to form near the low and along the cold front, where instability and shear will also favor supercells with large hail and perhaps tornado risk. Given the potential for early storms, this lends uncertainty to the forecast, and precludes an upgrade of higher coverage probabilities as placement would be uncertain. Regardless of early day evolution, moderate westerlies atop the expanding moist sector should favor areas of damaging wind, hail, and perhaps a few tornadoes during the day and through early evening. The severe risk could potentially reach into western OH and northern KY late, depending on upstream evolution. ...Northern TX... A cold front will push quickly south across OK and MO during the day, and across the Red River during the late afternoon and early evening. Given the late frontal arrival, strong destabilization will occur with full heating and upper 60s to lower 70s F dewpoints. MLCAPE over 3000 J/kg is forecast, with steep lapse rates through a deep layer. Although shear will not be strong, hodographs will favor southeastward-moving cells developing near the front or within the narrow low-level lapse rate plume where it will become uncapped. Locally damaging downbursts along with hail will be possible with any storms that develop, warranting an upgrade in severe probabilities for this focused diurnal event. ..Jewell.. 04/17/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY AND LOWER GREAT LAKES...AND IN PARTS OF NORTHEAST KANSAS AND WESTERN MISSOURI... ...SUMMARY... Scattered thunderstorms, capable of wind damage, isolated large hail and a tornado threat, are expected to develop across parts of the Ohio Valley and Lower Great Lakes this afternoon. Storms with large hail are expected tonight in parts of the central Plains and Ozarks. ...Ohio and Tennessee Valleys/Central Gulf Coast States... A negatively tilted upper-level trough, and an associated surface low, will move into the Great Lakes today. A corridor of maximized surface dewpoints will move eastward across the Ohio Valley today, as a cold front approaches from the west. Scattered thunderstorms will likely develop during the late morning, as low-level convergence and instability increases. These storms, in the form of clusters or short line segments, will move eastward across the Ohio Valley and Lower Great Lakes region during the afternoon. RAP forecast soundings across far eastern Indiana and western Ohio during the early afternoon show a favorable environment for severe storms, with MLCAPE near 1500 J/kg and 0-6 km shear around 50 knots. This should support an isolated large hail threat with the more discrete rotating storms. A wind-damage threat will also be possible, especially with the more organized line segments. Forecast soundings suggest that low-level shear will become more favorable in the late afternoon, with 0-3 km storm-relative helicity increasing into the 225 to 250 m2/s2 range. For this reason, the tornado threat is expected to be greater a bit further east from central and eastern Ohio into far western Pennsylvania. Further south into the Tennessee Valley and central Gulf Coast states, isolated thunderstorms are expected to develop ahead of a cold front, and near a moist axis with surface dewpoints in the 60s F. MLCAPE in the 750 to 1000 J/kg range, along with 0-6 km shear from 40 to 50 knots will be sufficient for an isolated severe threat. Marginally severe wind gusts and hail will be the primary threats. ...Central Plains/Ozarks... An upper-level trough will move through the north-central U.S. tonight, as a 70 to 80 knot mid-level jet passes through the trough. In response, a 40 to 50 knot low-level jet will develop further south across the central Plains. Thunderstorms are expected to initiate near the northern edge of the low-level jet late this evening from central Kansas into far southeast Nebraska. These storms are expected to move eastward across northeast Kansas and into western Missouri. Forecast soundings in northeast Kansas around 06Z have MUCAPE near 2500 J/kg, with effective shear around 45 knots. This, combined with 700-500 mb lapse rates around 7.5 C/km, should be favorable for elevated rotating storms with potential for very large hail. The large hail threat is expected to be greatest in the 04Z to 07Z time window, but may persist through late in the period. ..Broyles/Lyons.. 04/17/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY AND LOWER GREAT LAKES...AND IN PARTS OF NORTHEAST KANSAS AND WESTERN MISSOURI... ...SUMMARY... Scattered thunderstorms, capable of wind damage, isolated large hail and a tornado threat, are expected to develop across parts of the Ohio Valley and Lower Great Lakes this afternoon. Storms with large hail are expected tonight in parts of the central Plains and Ozarks. ...Ohio and Tennessee Valleys/Central Gulf Coast States... A negatively tilted upper-level trough, and an associated surface low, will move into the Great Lakes today. A corridor of maximized surface dewpoints will move eastward across the Ohio Valley today, as a cold front approaches from the west. Scattered thunderstorms will likely develop during the late morning, as low-level convergence and instability increases. These storms, in the form of clusters or short line segments, will move eastward across the Ohio Valley and Lower Great Lakes region during the afternoon. RAP forecast soundings across far eastern Indiana and western Ohio during the early afternoon show a favorable environment for severe storms, with MLCAPE near 1500 J/kg and 0-6 km shear around 50 knots. This should support an isolated large hail threat with the more discrete rotating storms. A wind-damage threat will also be possible, especially with the more organized line segments. Forecast soundings suggest that low-level shear will become more favorable in the late afternoon, with 0-3 km storm-relative helicity increasing into the 225 to 250 m2/s2 range. For this reason, the tornado threat is expected to be greater a bit further east from central and eastern Ohio into far western Pennsylvania. Further south into the Tennessee Valley and central Gulf Coast states, isolated thunderstorms are expected to develop ahead of a cold front, and near a moist axis with surface dewpoints in the 60s F. MLCAPE in the 750 to 1000 J/kg range, along with 0-6 km shear from 40 to 50 knots will be sufficient for an isolated severe threat. Marginally severe wind gusts and hail will be the primary threats. ...Central Plains/Ozarks... An upper-level trough will move through the north-central U.S. tonight, as a 70 to 80 knot mid-level jet passes through the trough. In response, a 40 to 50 knot low-level jet will develop further south across the central Plains. Thunderstorms are expected to initiate near the northern edge of the low-level jet late this evening from central Kansas into far southeast Nebraska. These storms are expected to move eastward across northeast Kansas and into western Missouri. Forecast soundings in northeast Kansas around 06Z have MUCAPE near 2500 J/kg, with effective shear around 45 knots. This, combined with 700-500 mb lapse rates around 7.5 C/km, should be favorable for elevated rotating storms with potential for very large hail. The large hail threat is expected to be greatest in the 04Z to 07Z time window, but may persist through late in the period. ..Broyles/Lyons.. 04/17/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY AND LOWER GREAT LAKES...AND IN PARTS OF NORTHEAST KANSAS AND WESTERN MISSOURI... ...SUMMARY... Scattered thunderstorms, capable of wind damage, isolated large hail and a tornado threat, are expected to develop across parts of the Ohio Valley and Lower Great Lakes this afternoon. Storms with large hail are expected tonight in parts of the central Plains and Ozarks. ...Ohio and Tennessee Valleys/Central Gulf Coast States... A negatively tilted upper-level trough, and an associated surface low, will move into the Great Lakes today. A corridor of maximized surface dewpoints will move eastward across the Ohio Valley today, as a cold front approaches from the west. Scattered thunderstorms will likely develop during the late morning, as low-level convergence and instability increases. These storms, in the form of clusters or short line segments, will move eastward across the Ohio Valley and Lower Great Lakes region during the afternoon. RAP forecast soundings across far eastern Indiana and western Ohio during the early afternoon show a favorable environment for severe storms, with MLCAPE near 1500 J/kg and 0-6 km shear around 50 knots. This should support an isolated large hail threat with the more discrete rotating storms. A wind-damage threat will also be possible, especially with the more organized line segments. Forecast soundings suggest that low-level shear will become more favorable in the late afternoon, with 0-3 km storm-relative helicity increasing into the 225 to 250 m2/s2 range. For this reason, the tornado threat is expected to be greater a bit further east from central and eastern Ohio into far western Pennsylvania. Further south into the Tennessee Valley and central Gulf Coast states, isolated thunderstorms are expected to develop ahead of a cold front, and near a moist axis with surface dewpoints in the 60s F. MLCAPE in the 750 to 1000 J/kg range, along with 0-6 km shear from 40 to 50 knots will be sufficient for an isolated severe threat. Marginally severe wind gusts and hail will be the primary threats. ...Central Plains/Ozarks... An upper-level trough will move through the north-central U.S. tonight, as a 70 to 80 knot mid-level jet passes through the trough. In response, a 40 to 50 knot low-level jet will develop further south across the central Plains. Thunderstorms are expected to initiate near the northern edge of the low-level jet late this evening from central Kansas into far southeast Nebraska. These storms are expected to move eastward across northeast Kansas and into western Missouri. Forecast soundings in northeast Kansas around 06Z have MUCAPE near 2500 J/kg, with effective shear around 45 knots. This, combined with 700-500 mb lapse rates around 7.5 C/km, should be favorable for elevated rotating storms with potential for very large hail. The large hail threat is expected to be greatest in the 04Z to 07Z time window, but may persist through late in the period. ..Broyles/Lyons.. 04/17/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY AND LOWER GREAT LAKES...AND IN PARTS OF NORTHEAST KANSAS AND WESTERN MISSOURI... ...SUMMARY... Scattered thunderstorms, capable of wind damage, isolated large hail and a tornado threat, are expected to develop across parts of the Ohio Valley and Lower Great Lakes this afternoon. Storms with large hail are expected tonight in parts of the central Plains and Ozarks. ...Ohio and Tennessee Valleys/Central Gulf Coast States... A negatively tilted upper-level trough, and an associated surface low, will move into the Great Lakes today. A corridor of maximized surface dewpoints will move eastward across the Ohio Valley today, as a cold front approaches from the west. Scattered thunderstorms will likely develop during the late morning, as low-level convergence and instability increases. These storms, in the form of clusters or short line segments, will move eastward across the Ohio Valley and Lower Great Lakes region during the afternoon. RAP forecast soundings across far eastern Indiana and western Ohio during the early afternoon show a favorable environment for severe storms, with MLCAPE near 1500 J/kg and 0-6 km shear around 50 knots. This should support an isolated large hail threat with the more discrete rotating storms. A wind-damage threat will also be possible, especially with the more organized line segments. Forecast soundings suggest that low-level shear will become more favorable in the late afternoon, with 0-3 km storm-relative helicity increasing into the 225 to 250 m2/s2 range. For this reason, the tornado threat is expected to be greater a bit further east from central and eastern Ohio into far western Pennsylvania. Further south into the Tennessee Valley and central Gulf Coast states, isolated thunderstorms are expected to develop ahead of a cold front, and near a moist axis with surface dewpoints in the 60s F. MLCAPE in the 750 to 1000 J/kg range, along with 0-6 km shear from 40 to 50 knots will be sufficient for an isolated severe threat. Marginally severe wind gusts and hail will be the primary threats. ...Central Plains/Ozarks... An upper-level trough will move through the north-central U.S. tonight, as a 70 to 80 knot mid-level jet passes through the trough. In response, a 40 to 50 knot low-level jet will develop further south across the central Plains. Thunderstorms are expected to initiate near the northern edge of the low-level jet late this evening from central Kansas into far southeast Nebraska. These storms are expected to move eastward across northeast Kansas and into western Missouri. Forecast soundings in northeast Kansas around 06Z have MUCAPE near 2500 J/kg, with effective shear around 45 knots. This, combined with 700-500 mb lapse rates around 7.5 C/km, should be favorable for elevated rotating storms with potential for very large hail. The large hail threat is expected to be greatest in the 04Z to 07Z time window, but may persist through late in the period. ..Broyles/Lyons.. 04/17/2024 Read more

WW 0120 Status Updates
STATUS REPORT ON WW 120 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 ESE MLI TO 25 SW RFD TO 10 N RFD TO 10 SE MSN. REMAINING VALID PORTION OF WW 120 MAY BE ALLOWED TO EXPIRE AT 17/03Z. ..KERR..04/17/24 ATTN...WFO...LOT...MKX... STATUS REPORT FOR WT 120 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC007-037-099-103-141-201-170300- IL . ILLINOIS COUNTIES INCLUDED ARE BOONE DE KALB LA SALLE LEE OGLE WINNEBAGO WIC055-105-127-170300- WI . WISCONSIN COUNTIES INCLUDED ARE JEFFERSON ROCK WALWORTH THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 120 TORNADO IL WI 162250Z - 170300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 120 NWS Storm Prediction Center Norman OK 550 PM CDT Tue Apr 16 2024 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Northern Illinois Southern Wisconsin * Effective this Tuesday afternoon and evening from 550 PM until 1000 PM CDT. * Primary threats include... A couple tornadoes possible Scattered damaging wind gusts to 70 mph possible Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Scattered storm clusters and a couple of supercells will be possible this evening into north central Illinois and south central Wisconsin near a surface warm front. A couple of tornadoes, damaging gusts of 60-70 mph and large hail of 1-1.5 inches in diameter will all be possible through late evening. The tornado watch area is approximately along and 25 statute miles east and west of a line from 25 miles north of Janesville WI to 65 miles south southwest of Rockford IL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...CONTINUE...WW 116...WW 117...WW 118...WW 119... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 23035. ...Thompson Read more

MD 0468 CONCERNING TORNADO WATCH 117...120... FOR PATS OF FAR EASTERN IOWA...CENTRAL/NORTHERN ILLINOIS...AND FAR SOUTHERN WISCONSIN
Mesoscale Discussion 0468 NWS Storm Prediction Center Norman OK 0732 PM CDT Tue Apr 16 2024 Areas affected...pats of far eastern Iowa...central/northern Illinois...and far southern Wisconsin Concerning...Tornado Watch 117...120... Valid 170032Z - 170200Z The severe weather threat for Tornado Watch 117, 120 continues. SUMMARY...The risk for damaging winds, hail, and a couple of tornadoes continues. Local extensions of WW117 may be needed across parts of IL this evening. DISCUSSION...The ongoing cluster of thunderstorms over eastern IA is expected to move into western IL and southern WI in the next hour. Buoyancy generally decreases with north/eastward extent as previous convection has overturned the air mass south of the nearly stationary warm front. Still, 500-1000 J/kg of MLCAPE and strong deep-layer shear will allow storms to stay organized farther east into IL early this evening. Damaging winds appear to be the most likely threat given the linear mode, but hail and a couple of tornadoes will remain possible. Strong to severe storms may linger over parts of far southeast IA and into western/central IL after the planned 01z expiration of WW118. Convective trends will be monitored and a local extension could be necessary. ..Lyons/Thompson.. 04/17/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LOT...ILX...MKX...LSX...DVN...ARX... LAT...LON 39999044 40139091 40449118 40909124 42679041 43309008 43388972 43248926 43098872 42778858 42208880 41548893 41218906 40298949 39999044 Read more

WW 0120 Status Updates
STATUS REPORT ON WW 120 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 ESE DBQ TO 15 WSW MSN TO 20 NW MSN. ..LYONS..04/17/24 ATTN...WFO...LOT...MKX... STATUS REPORT FOR WT 120 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC007-037-099-103-141-201-170240- IL . ILLINOIS COUNTIES INCLUDED ARE BOONE DE KALB LA SALLE LEE OGLE WINNEBAGO WIC025-045-105-170240- WI . WISCONSIN COUNTIES INCLUDED ARE DANE GREEN ROCK THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

MD 0467 CONCERNING SEVERE THUNDERSTORM WATCH 119... FOR PARTS OF NORTHEAST AND EAST CENTRAL MISSOURI
Mesoscale Discussion 0467 NWS Storm Prediction Center Norman OK 0623 PM CDT Tue Apr 16 2024 Areas affected...Parts of northeast and east central Missouri Concerning...Severe Thunderstorm Watch 119... Valid 162323Z - 170130Z The severe weather threat for Severe Thunderstorm Watch 119 continues. SUMMARY...The risk for widely scattered additional strong to severe thunderstorm development near/east of Columbia and Jefferson City into areas northwest of St. Louis may still not be negligible. However, it appears to be lowering and likely to diminish further with the loss of daytime heating. If current trends continue, the watch may be cancelled within the next hour or so. DISCUSSION...In the wake of an initial band of weakening convection which has spread east of the Mississippi River, a moistening low-level environment has contributed to a corridor of increasing potential instability across much of northeastern into east central and south central Missouri. This is ahead of a remnant dryline advancing across/east of the Kirksville, Columbia and Springfield vicinities. Renewed discrete thunderstorm development is ongoing as far south as areas to the southeast of Kirksville, with additional deepening convection noted near/west of Columbia and Jefferson City. Some convection allowing guidance, including the High Resolution Rapid Refresh suggest further intensification of the southern convective development might still be possible, before spreading near/to the northwest of the Greater St. Louis area through 00-02Z. Based on the Rapid Refresh forecast track of a weakening 500 mb jet core, and associated mid-level subsidence/warming, this would seem be the southern/southeastern limit for stronger convective development. However, based on latest water vapor imagery, the potential for new storms south of the Hannibal/Quincy area is becoming low. ..Kerr.. 04/16/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILX...LSX... LAT...LON 39749206 40139168 40019060 39389045 38759092 38429160 38519240 39079239 39749206 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0800 PM CDT Tue Apr 16 2024 Valid 170100Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID TO UPPER MISSISSIPPI VALLEY INTO THE SOUTHWESTERN GREAT LAKES AND LOWER OHIO VALLEY... ...SUMMARY... Several clusters of strong to severe storms will continue to impact the mid to upper Mississippi Valley this evening. The severe threat will affect the southwestern Great Lakes and lower Ohio Valley later tonight. Damaging wind gusts, isolated large hail, and a few tornadoes will be possible. ...Mid to Upper Mississippi Valley/Southwestern Great Lakes/Lower Ohio Valley... An upper-level low is evident on water vapor imagery over the mid Missouri Valley, with an associated 60 to 80 knot mid-level jet located in the mid Mississippi Valley. At the surface, a 989 mb low is located in far northwest Iowa, with a corridor of maximized low-level moisture (surface dewpoints in the 60s F) in the mid to upper Mississippi Valley. A line of strong to severe thunderstorms is ongoing along a zone of low-level convergence from northwest Illinois into southern Wisconsin. This line will likely be maintained, moving east-northeastward to the western shore of Lake Michigan by late this evening. Ahead of the line, the RAP has MLCAPE in the 1000 to 1500 J/kg range. WSR-88D VWPs in central and northern Illinois have 0-6 km shear around 60 knots suggesting the severe threat will continue this evening. Wind damage will be likely with the more intense parts of the line, especially with the faster moving bowing segments. WSR-88D VWPs across central and northern Illinois have 0-3 storm-relative helicity generally in the 500 to 550 m2/s2 range. This will likely continue to support an isolated tornado threat with rotating storms that remain somewhat discrete, or with circulations within the line itself. Isolated large hail could also accompany the stronger rotating cells. Further south into the mid Mississippi Valley, the RAP is analyzing MLCAPE in the 1200 to 1500 J/kg range across much of eastern Missouri and Arkansas. The instability combined with 0-6 km shear in the 60 to 75 knot range will likely support a severe threat this evening. However, large-scale ascent is weaker this far south suggesting that storm coverage will be isolated. Any cell that can intensify near the instability axis this evening, could be associated with wind damage and hail. A marginal tornado threat will also be possible. ..Broyles.. 04/17/2024 Read more